Lasers Help Weigh Dinosaurs

A new technique can estimate a body's volume and weight based on laser scans of its skeleton. Sophie Bushwick reports

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Some dinosaurs were really huge. And now we may have a better way to estimate just how heavy these giants were. Researchers have developed a method to weigh dinosaurs, based on laser scans of their skeletons. The study is in the journal Biology Letters. [W. I. Sellers et al.,"Minimum convex hull mass estimations of complete mounted skeletons"]

Looking at a bare human skeleton, how would you guess whether its owner was chubby or svelte? If you calculated how much space the fully-fleshed body occupied, you could multiply that volume by tissue density to find the weight.

Researchers laser-scanned 14 modern mammal skeletons to create digital models of each body. These 3-D models were unrealistically scrawny, with skin stretched tight over the bones. But their undersized volumes were consistent, measuring in as 21 percent less than the actual animals.


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Based on this information, the researchers scanned Giraffatitan bones, added 21 percent to the digital model’s volume, and then calculated the dinosaur’s weight: about 51,000 pounds. The technique could become the preferred way to estimate mass based on skeletons, improving our understanding of how extinct species lived and moved. And helping paleontologists make earth-shaking discoveries.

—Sophie Bushwick

[The above text is a transcript of this podcast.]

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